1. Field
Embodiments of the present disclosure relate to an image forming apparatus and a control method thereof which execute auto color registration.
2. Description of the Related Art
In general, a color image forming apparatus prints an image on a sheet of paper using four colors, e.g., yellow, magenta, cyan and black. The color image forming apparatus executes auto color registration (ACR) to precisely register respective colors at desired positions of a sheet of paper. Through ACR, relative positions of the four colors are compensated such that images of the four colors are correctly registered on the sheet of paper. Further, through ACR, test patterns of the respective colors are printed one by one on printing medium, intervals between the test patterns of the respective colors are detected, and a distortion degree is compensated according to a result of the detection.
After conditions to execute ACR are set, the color image forming apparatus executes ACR if a current state satisfies the set conditions. These conditions may include a case in which a temperature variation of a laser scanning unit (LSU) for a specific time is greater than a reference value, a case in which the total number of printed sheets of paper becomes twice a set number, a case in which a cover of the apparatus is opened or closed, and a case in which consumption goods, such as a toner, are replaced.
Further, the conventional image forming apparatus executes ACR under the condition that a mechanical change factor due to photoconductors or drive rollers is not considered, or executes ACR under the condition that the mechanical change factor due to only one of the photoconductors and the drive rollers is considered.